Just last year, Crystal renn reveled in her plus-size figure on the cover of her memoir, "Hungry" (below). But on the catwalk for Chanel this year, she was a shadow of her former self.Pascal Le Segretain/WireImage.co

(AP)

COME on, modeling industry — what are you doing to Crystal Renn?

New photos of the plus-size beauty have emerged that appear, as her friend and fellow plus-size model Kate Dillon admits, like “heroin chic.”

In May, Renn walked the runway for Chanel in St. Tropez, sporting jutting cheekbones and a tight dress that made her look at least two sizes smaller than the size 10 she claims to be. Then this month her agency, Ford Models, released shocking pictures of her on fordmodelsblog.com. In the shoot taken for a charity by photographer Nicholas Routzen, the 24-year-old model’s eyes look sunken and her face drawn, as she barely wears a T-shirt that skims her skinny, naked legs.

Blogs are now crying “Feed Crystal Renn.” And while Renn still looks fleshier than famously emaciated mannequins such as Kate Moss, fans’ fears aren’t totally unwarranted. Renn, after all, is a woman who’s battled anorexia in the past and says the modeling industry’s pressure to be thin nearly killed her.

“She’s lost some weight,” acknowledges Dillon, 36, but claims Renn shed the pounds during a recent hiking trip to Patagonia. “The one thing that’s so great about plus-size models is that we’re allowed to fluctuate much more than other models. A plus-size model doesn’t have to be a size 12 for the rest of her life. If she gets a new workout regimen and drops to a size 8, it’s not that big of a deal.”

Or is it?

Last year, Renn released her memoir titled “Hungry: A Young Model’s Story of Appetite, Ambition and the Ultimate Embrace of Curves.” She described first coming to New York at age 16, signing a $250,000 modeling contract and starving herself to stay at 95 pounds. Eating less than 1,000 calories a day, worrying if a few pieces of sugarless gum might add to her figure, Renn says she became asexual and lost her period along with her sunny personality. At one point, a photographer screamed at her that she was “huge” when she went up to 130 pounds, which was her breaking point and led to a long period of binge eating.

After jumping to a size 16, Renn finally settled into a size 12 — which is when she achieved true success. She appeared in Teen Vogue in 2004 and even landed inside the pages of Glamour and US Vogue. She was widely touted as “the world’s most successful plus-size model” — a title she reveled in.

“I [decided] to be a plus-size model and let my body be what it was meant to be,” she told The Post in September. “Women are taught that if they get skinny, their lives will be perfect. But real life doesn’t work that way. I’m here to prove it.” (She declined to be interviewed for this article.)

Strangely, now that Renn seems to have achieved superstardom — and happiness — as a plus-size model, she appears to be getting thin again.

Insiders blame the modeling industry. Despite its token embrace of “curvier figures” in the past year (Renn was the poster girl for trendy V magazine’s “Size” issue in January), many say the fashion world will never accept women with a little extra meat on their bones.

“Any woman in fashion and Hollywood [who’s] in the spotlight — as soon as you get any attention, it all goes back to your weight,” says one industry insider who promotes high-end fashion labels. “It’s almost like a disease. No matter how self-empowered you are, there is always someone telling you, ‘You have to be thinner.’

“The only thing a lot women can control is their weight,” she adds, pointing to Jennifer Hudson who — once the symbol of being big and proud of it — is now gracing the cover of this week’s People magazine proclaiming: “My New Body. WOW! Size 16 to Size 6!”

“I wouldn’t be surprised if designers said [to Renn], ‘If you want to keep going, you have to lose the weight.’ ”

Olga Liriano, a casting agent who used to book models for Harper’s Bazaar, concurs. “Crystal Renn starts doing Chanel shows and maybe feels this pressure to drop some weight now that she’s getting more attention. There seems to be no role model for just being your weight.”

Michael Gross, author of “Model: The Ugly Business of Beautiful Women,” agrees that the Chanel show, cast by designer Karl Lagerfeld, may have been the tipping point. “The very fact that Karl Lagerfeld, who has railed against weight, hired her would say that she’s probably lost some weight, because it’s highly unlikely that Karl Lagerfeld will bend to the weight of public opinion.”

What kind of a message does it send? “It sends the message that models should not be role models,” Gross says. “Models are fantasies in the pages of magazines. Little girls should not grow up wanting to be models. It’s like growing up wanting to be Barbie.”

Still, Renn’s agent, Gary Dakin, defends Renn, saying she is still a size 10. “She knows how to move, and she can angle herself to whatever position,” Dakin says. “She knows how to work lighting. I understand that in the [Ford Models] picture she looks smaller, but I also understand that the industry does things that can make models appear differently. Crystal ranges between a 10 and 12, but she’s never not been a 10. I’m telling you, I measure her. I physically measure her.”

Her friend Dillon guesses she’s closer to a size 8 now. “She looks like a size 8, 10. She’s definitely not a size 4 or 2. I know she loves herself now. She went on a big hiking trip, and she had a physical awakening as to how good it feels.”

Her agent reiterates, “She’s just getting into hiking. She’s not losing weight. You know she’s just very, very, very, very healthy.”

Hopefully this is the case because, as physician Wayne Anderson, the author of “Habits of Health” who specializes in weight loss, says, “When people lose weight quickly, they can get that sunken look. It can lead to long-term poor health, so it’s not a good image for these extra-thin models. Most of them are starving themselves.”

Unfortunately, the pressure is always on when you’re a specialty model. “There’s always been one slot for a famous plus-sized model,” Gross says. “And it’s a simple fact of the modeling business that models stay famous by constantly reinventing themselves. So maybe Crystal Renn just created a job opening.”